Stitchless seam system for joining laminates

ABSTRACT

A stitchless seam between a first panel having a functional layer and a second panel having a functional layer is provided. The seam system is formed via a discontinuous fused stitchless seam which connects a first panel to a second panel. A reinforcement may be used to strengthen the discontinuous fused stitchless seam connecting the first panel to the second panel, allowing formation of a liquid-impervious stitchless seam system. A method for forming the system is also provided.

BACKGROUND OF THE INVENTION

The present invention relates to a stitchless seam system betweenlaminates which results in a functionally liquid-proof stitchless seamwidth created between adjacent panels of laminates. The stitchless seamsystem is of use in the construction of high performance waterproofapparel and footwear. While traditional fused seams are useful in liquidproof garments, such seams tend to be rather stiff. Further, thecontinual flexing of the stitchless seam leads to a reduced lifespan ofthe garment. The stitchless seam of the present invention allows theformation of seams of very small dimension which provide flexibility andretain the integrity of the seam to prevent cracking. The use of coatedtextile composites or laminates of textiles and liquid protectivebarrier membrane layers to create liquid-proof protective apparel andprotective footwear is known in the industry. The most common of theseapplications is waterproof breathable apparel. Typical examples arelaminate materials sold by W.L. Gore and Associates, Inc. under theregistered trade name GORE-TEX, which contain a waterproof breathablefilm laminated, or bonded, to one or more textile layers. Theselaminates are fabricated into apparel and footwear and sold as GORE-TEX®garments and the like. Coated textiles can also be used in textilecomposites for these same purposes.

Pieces or panels of these laminates are joined together to form garmentsand other similar textile structures. In the case of footwear, pieces orpanels of laminates are typically joined together to form booties whichare then integrated as a liner in the shell of the footwear and combinedwith the sole. For the garments and footwear to be liquid proof andprotective, there is a need to seal the seams where the panels oflaminate are joined together. The joining of these laminate panels istypically done by first sewing the laminates together using conventionalsewing techniques. Liquid-proof sealing of these sewn seams is thenaccomplished by the application of a seam seal tape having athermoplastic hot-melt adhesive which seals to the surface of thecoating or protective barrier film and creates a seal over the sewingholes and the area where the layers join between the stitches. The seamseal tape may be heated, for example, using a nozzle to direct a streamof hot air so as to melt the adhesive. The tape is then applied over theseam and both are passed through the nip of a pair of pressure rollersin order to squeeze the molten adhesive onto the protective layersurface to ensure good bonding of the tape to the surface. For aestheticreasons, the seam sealing tape is generally applied to the interior of agarment so that it is hidden from view. In the case of a bootie forcovering the foot, the seam sealing tape is generally applied to theexterior of a bootie which is between the lining material and the shellof the footwear so that it is hidden from view. Less common sealingtechniques such as gluing and fusing are also known in the art.

Different fused seams have been disclosed in the art, but none of theprior art teaches the present invention. U.S. Pat. No. 6,797,088discloses a method for connection of pieces of textile fabric. In thismethod, a cut edge is formed and the threads bound at the cut edge ofeach of the textile pieces. The textile pieces are then laid on eachother in an overlapping manner and the pieces are pressed togetherbetween a sonotrode and an anvil. At least one of the sonotrode or anvilhas a surface profile with a number of elevations. The textile piecesare connected by ultrasonic oscillation of the sonotrode. The pattern ofelevations in the sonotrode and/or anvil results in fusion orplasticization of the textile pieces at particular points only whileleaving textile fabric at other points. Thus, a discontinuousultrasonically fused seam is produced.

U.S. Pat. No. 6,103,325 discloses an ultrasonically formed seamcomprising a laminate sheet constructed solely of a polyester fabric onone side and a polyurethane coating on the other side of the sheet. Toform the seam, sides of the fabric coated with polyurethane are broughtinto contact and ultrasonic energy is applied to fuse the fabricstogether to form a unitary, monolithic fluid-proof seam;

Publication No. WO2005/000055 discloses a fused seam between the edgesof two laminates wherein each textile layer is made up of two componentswith different melting temperatures. The seam is formed by the meltedsecond component and the non-melted first component of the textilelayers of each laminate. Edges of the seamed laminates are in anedge-to-edge butt orientation.

Publication No. US2003/0135185 discloses adhesiveless absorbentgarments, the components of which are held together by one or moreadhesiveless bonds. In one embodiment, the adhesiveless bonds are formedultrasonically.

A need exists in the garment and footwear industry for a reliable andeffective technique for joining two or more panels of a complex ormulti-layered textile laminate construction to form a flexibleliquid-proof seam in garments and protective footwear. There is afurther need in the industry for a liquid-proof fused seam whichexhibits flexibility, durability, strength, and crack resistance. Thepresent invention solves the need of the industry.

Definitions

“Panels” are laminates with at least one barrier layer and at least oneadditional layer, such as a textile, non-woven, or other suitablesubstrate layer.

Panels may further comprise coated textiles, protective layers,barriers, membranes, or films.

“Protective layer”, “barrier layer”, “functional layer”, or “film” aredefined as a film or coating that provides a barrier to liquid waterpenetration as a minimum, and ideally to a range of liquid chemicalchallenges. The layer is considered liquid proof if it prevents liquidwater penetration against a pressure of at least 0.07 bar for a durationof at least 3 minutes. The protective layer material preferablyguarantees a water penetration pressure of more than 0.07 bar. The waterpenetration pressure is measured on a liquid-proof panel based on thesame conditions described with respect to the Suter Test forLiquid-proof Seams, described herein.

“Seam” is defined as the area where 2 or more panels are permanentlyjoined together by sewing, gluing, fusing, or other mechanical joining.

“Liquid-proof seam” is a stitchless seam that will not leak or weepliquid when challenged with a test fluid at a pressure of at least 0.07bar for a duration of at least 3 minutes. The test fluid is at minimumwater, and ideally can be a range of liquid chemicals.

“Garments” is defined as apparel including coats, jackets, shirts,pants, suits, gloves, hats, or other structures formed from joinedlaminate panels.

“Footwear” is defined as a covering for the foot, such as a shoe, boot,sock, or the like, which incorporates one or more laminate panelsincluding a protective layer, said laminate panels being joined togetherby at least one durably liquid-proof seam. The laminate panels may forma bootie as a liner within the footwear, or alternatively the joinedlaminate panels may comprise both liner and upper of the footwear whenattached to or with other components of the footwear.

“Discontinuous seam” is defined as a seam with broken areas; oralternately at least one continuous fused stitchless seam with points invarying proximity to the cut edge.

“Reinforcement” is defined as any material suitable to increase thestrength of a seam connecting a first panel to a second panel. Areinforcement may provide a liquid-impervious seam. The reinforcementtraverses the discontinuous fused seams and joins a first panel to thesecond panel.

“Seam width” is defined as the distance from the cut edge of a panel tothe seam portion most distal to the cut edge.

SUMMARY OF THE INVENTION

The present invention provides a liquid-proof stitchless seam systembetween at least two panels. The system comprises a first panel having afunctional liquid-proof layer; a second panel having a functionalliquid-proof layer; and a discontinuous seam connecting the first panelto the second panel. A reinforcement may be added which strengthens thediscontinuous seam connecting the first panel to the second panelproviding a liquid-impervious seam.

The present invention further provides a liquid-proof stitchless seambetween panels comprising a first panel having a functional liquid-prooflayer and a second panel having a functional liquid-proof layerconnected by a first discontinuous seam. The first discontinuous seamconnects the first panel to the second panel; and a second seam may beadded which strengthens the first discontinuous seam connecting thefirst panel to the second panel providing a liquid-impervious seam.

Further provided is a method of forming a fused liquid-proof stitchlessseam by joining together pieces of liquid-proof laminate. This isachieved by placing at least two pieces of a liquid-proof laminate eachhaving at least a textile layer and a liquid-proof functional layer instacked relation with their textile regions in contact with one anotherto form seam width area defining the positioning of a stitchless seamline. Heat and pressure are than applied to the stacked laminates alongthe seam width, the heat being applied continuously and the pressurebeing applied at a constant interval most proximal to the edge of thestitchless seam line forming a continuous stitchless seam and atspaced-apart intervals juxtaposed to the continuous stitchless seam toform a discontinuous stitchless seam thereby forming multiple seamsalong the seam region. The continuous stitchless seam may be a cut weldseam. A reinforcement may be added to strengthen the bond betweenpanels.

DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1F show schematic drawings representing two panels joined by adiscontinuous fused seam.

FIG. 2 shows a cross sectional view of a three-layer laminate prior tofusing, sewing, or sealing.

FIG. 3 shows a cross sectional view of two three-layer laminate panelsthat are bonded via a discontinuously fused seam configuration formed byan embossing rib.

FIG. 4 shows a cross sectional view of another embodiment of adiscontinuous seam configuration between three-layer laminate panelswith a reinforcement bridging over the seam and adhering to the cut endsand interior sides of the panels.

FIG. 5 shows a cross sectional view of a two-layer laminate panel wherethe complex textile structure has been fused to form a discontinuousstitchless seam region.

FIG. 6 shows a top perspective view of a discontinuous stitchless seamused to join two laminate panels; in this view the cut edge is pressedto one side.

FIG. 7 shows a side view schematic of a sonic welder with two panels ina stacked relationship to each other.

FIG. 8 shows a cross-sectional view of an ultrasonic fusing wheel with acutting rib.

FIGS. 9-14 show various contemplated discontinuous seam patterns.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a stitchless seam system 1 formed byfused garment panels such as liquid-proof laminates with a continuousstitchless seam adjacent to a discontinuous stitchless seam. In apreferred embodiment of the present invention, the stitchless seamsystem 1 comprises two or more panels of laminate ultrasonically fusedto form at least one continuous stitchless seam adjacent to one or morediscontinuous stitchless seams. The stitchless seam system 1 of thepresent invention is well suited for formation between panels which arefunctionally liquid proof.

FIGS. 1A-1F show the present invention in its simplest embodiment, as astitchless seam system 1 formed between at least two panels via adiscontinuous seam 6, shown as connecting the first panel 5 to thesecond panel 7. The panels comprise an exterior side 8, an interior side10, and a cut edge. The panels are joined in a stacked relation via adiscontinuous seam 6. The cut edge 12 may also have a cut weld 14 formedat the perimeter of the panels. The cut weld 14 may be formed by acutting wheel or ultrasonic fusion. The distance between the cut edgeand the most distal portion of the discontinuous seam 6 is referred toas the seam width 15. The term discontinuous seam 6 refers to astitchless seam wherein the bonded edges parallel to and fartherest fromthe cut edges of the panels are discontinuous. Suitable types of fusinginclude ultrasonic, radio-frequency (RF), thermal, adhesives, localizedthermal bonding. A secondary seam may be used with the discontinuousseam 6 to form the stitchless seam system 1 of the present invention. Asshown in FIGS. 1B, 1C, 1E, and 4, the stitchless seam system 1 mayfurther comprise a reinforcement 5 for added durability and/or strength.

It is to be noted that a discontinuous stitchless seam system 1 (FIGS.1A-1E, and 3-6) may be comprised of a fused stitchless seam with brokenareas; or alternately at least one continuous fused stitchless seam withpoints in varying proximity to the cut edge as shown in FIG. 1F. One ormore seams oriented essentially parallel to the cut edge in the seamregion make up the seam width 15. Depending upon the seam width and thedistance between multiple seams, the seam system width will vary. FIG. 2shows a panel 4 comprising a multi-layer laminate useful in the presentinvention. The multi-layer laminate comprises an exterior side 8, aninterior side 10, and a functional layer 9. The functional layer 9 maybe a membrane, a film, a laminate comprising a polytetrafluoroethylene(PTFE), expanded PTFE, polyurethanes, or other suitable substrates. Thefunctional layer may provide the panel with a functionally liquid-prooffilm or membrane that will not leak or weep when challenged with a testfluid at a pressure of at least 0.07 bar for a duration of at leastthree minutes. The individual layers making up the laminate may bebonded via an adhesive 13 or may be otherwise joined.

In one embodiment as shown in FIGS. 1B and 1C, a reinforcement 5 may beused with the discontinuous seam to increase the strength of thestitchless seam system 1 connecting the first panel 5 to the secondpanel 7 and providing a liquid-impervious seam. The reinforcement 5 maybe of any suitable material including: textile tapes, waterproof tapes,threads or waterproof textile laminates, thread, tape, Kevlar™,polyester, nylon, inelastic substrates, seam tape, textile laminate,sealing polymers, or other materials which as a whole providereinforcement 5 to the seam system when subjected to stress or wear. Thereinforcement 5 traverses the discontinuous fused seams and furtherjoins the first panel 5 to the second panel 7. A thin reinforcement 5 isdesired which sufficiently withstands strain and allows maximumflexibility. The reinforcement 5 may offer barrier properties. Thereinforcement 5 may be incorporated as a part of a seam tape. In thisaspect, the reinforcement 5 need not be as wide as the seam tape toallow the tape edges to achieve a thinner profile than that of the tapein proximity to the reinforcement 5. It is contemplated that adiscontinuous seam 6 may be used in conjunction with a sealing polymerto provide barrier properties. It is further contemplated that one ormore additional fused seams may be incorporated into the stitchless seamregion width. The one or more additional fused seams may be eithercontinuous, discontinuous, or a combination of the two types of fusedseams. It is preferred that the additional seams are heat welded. Thereinforcement 5 may be a multi-layer stitchless seam tape comprising atop layer, an adhesive layer, and a reinforcement 5. The reinforcement 5may be a distinct layer used to improve the seam strength, afterapplication applied to the fused seam. The reinforcement 5 may improvethe liquid proofness of the seam and/or improve the seam strength.Preferably the reinforcement 5 is applied to the inner side of aliquid-proof panel in an article. In one embodiment of the presentinvention the reinforcement 5 is in the form of a seam tape as shown inFIGS. 1B, 1C, and 1E. The seam tape may be secured on either side of theseam itself. For aesthetic reasons, the seam tape is usually applied tothe interior of a garment, so that it is hidden from view. Therefore,the seam tape is preferably secured to the lining side of a garment oraccessory. The seam tape may be a fusible adhesive tape, a fusibletextile tape, or a fusible laminate tape. One example of a fusible tapeis a weldable tape comprising at least one thermoplastic component whichis meltable at a temperature in the range 80° C. to 230° C. In anotherembodiment, the seam tape may be a thermoplastic film which softens andflows when heated. More usually, the seam tape comprises a backing tapehaving a covering of hot-melt adhesive on one side.

In one embodiment, after a discontinuous seam 6 has been producedaccording to the present invention, a seam tape (reinforcement 5) isheated, for example using a blast of hot air so as to melt the adhesive.The reinforcement 5 is then applied over the seam and both are passedthrough the nip of a pair of pressure rollers in order to squeeze themolten adhesive into the panels 4 so as to ensure good bonding of thereinforcement 5 to the underlying panels 4. The discontinuous seam 6 andthe seam tape on panels are transported continuously through thedistance and joined together. Any width of reinforcement 5 such as aseam tape may be used. However, the present invention also allows theuse of very thin, narrow seam tapes because of the thin fuseddiscontinuous seam 6 itself and the fact that there is no real seamallowance. Preferably the seam tape has a width of not more than 15 mm.For liquid-proof seams, it is advantageous to contiguously bond the seamtape to both panels and the seam width and cut weld regions of the seam,as shown in FIG. 4.

In another aspect the stitchless seam system 1 may further comprise acontinuous bond connecting the designated cut edge 12 of the first panel5 to the cut edge 12 of the second panel 7 in a stacked relation to eachother so that the exterior sides 8 of the panels are bonded to eachother, FIG. 1A. The fabric panels may be fused together at their edgesby a sonic fuse bead. As shown in FIG. 7, a sonic fuse may be formedwith a head having integral embossed fusing and cutting functions. Thesonic fuse bead is formed as the sonic welder 16 passes high frequencywaves through panels to join them. The discontinuous seam 6 is formed bylying two panels on top of each other with the outer facing textiles incontact with each other. A fused stitchless seam is created along oneedge of the layered laminate panels by moving the layered panels betweena rotating anvil 17 and sonotrode 18. The layers are run so that theanvil simultaneously cuts and fuses the edge of the panels together. Ina preferred embodiment, both the anvil and sonotrode speed settings arethe same.

The sonic waves vibrate the panels, creating heat through the frictionof one panel against another. The sonic fusing process essentially meltsor otherwise fuses the edges of the fabrics together. The head of thewelder, or anvil 17, may comprise a embossing rib 21 on a ultrasonicfusing wheel 20 having a profile thereon which determines the width ofthe sonic fuse bead made, as well as a cutting rib which is sharp enoughto trim extraneous portions of the fabric panels on the waste side ofthe discontinuous seam 6 at the time the seam is formed via sonicfusion. The cutting rib 23 may form either a discontinuous or acontinuously fused bond at the outer edge as it melts and cuts thepanels. When both a continuous and discontinuous bond are formed in theseam region, it is advantageous to orient the continuous bond parallelto and in close proximity to the discontinuous bond, to provide a narrowwidth stitchless seam region. The discontinuous bond may be formed invarying patterns including a cross-hatch pattern, a dotted pattern, asinusoidal pattern, or any other suitable pattern or stitchless seamedge design. FIGS. 9-14 show some examples of the discontinuous seamformed via an embossing rib 21. As can be seen, the embossed designs maybe of varying lengths, widths and patterns depending upon their desiredapplications.

In one aspect of the present invention, a stitchless seam system 1 isprovided which is impervious to liquids and comprises a first panel 5with a liquid-proof functional layer 9 having an exterior side 8, aninterior side 10, and a designated stitchless cut edge 12; a secondpanel 7 with a liquid-proof functional layer 9 having an exterior side8, an interior side, and a designated stitchless seam edge; and adiscontinuous bond connecting the designated stitchless seam edge of thefirst panel 5 to the designated stitchless seam edge of the second panel7 in a stacked relation to each other so that the exterior sides 8 ofthe panels are bonded to each other with the bonded areas most distantfrom the stitchless seam edges of the panels forming a discontinuouslybonded joint on the plane formed by the exterior sides 8 of the joinedpanels.

FIG. 8 shows a cross section of a fusing wheel 20 used to create adiscontinuous seam 6 via ultrasonic bonding. The fusing wheel 20comprises at least one circumferential discontinuous embossing rib 21mounted on the wheel which usually rotates around an axis 25. Theembossing rib 21 allows the panels to be bonded together withoutpuncturing the panels 4, at the points where the embossing rib contactsthe panels. The ultrasonic fusing wheel may further comprise acircumferential cutting rib 23, as shown in FIG. 8. It is preferred thatthe circumferential cutting rib 23 is mounted at least 0.1 mm from thediscontinuous embossing rib. The circumferential cutting rib 23 projectsfurther outward from the wheel than does the discontinuous embossing rib21. The stitchless seam allowance may be cut simultaneously with theapplication of the fused cutting seam or seams produced by the cuttingrib 23, or alternatively via a separate step.

The circumferential cutting rib and the discontinuous embossing rib arepreferably parallel to each other. However, it is foreseen that in somedesigns the discontinuous embossing rib and the cutting rib may not beparallel to each other. For instance, the discontinuous seam 6connecting the first panel 5 to the second panel 7 is applied at thesame time as the panels are cut on the designated stitchless seam edge.

The stitchless seam system 1 of the present invention is novel in thatthe stitchless seam is able to obtain strengths greater than 200 N atbreaking. Further, the stitchless seam system 1 of the present inventionis shown to withstand continuous wash and dry cycles for at leasttwenty-four hours without experiencing edge separation of the panels

A method is provided for forming a waterproof stitchless seam system 1.The seam system is formed by joining together pieces of waterprooflaminate so that at least two pieces of a waterproof laminate, eachhaving at least a textile layer and a liquid-proof functional layer 9,are placed in stacked relation with textile regions in contact with oneanother along a strip defining a seam region. Heat and pressure areapplied to the stacked laminates along said strip, with the heat beingapplied continuously and the pressure being applied at a constantinterval most proximal to the edge of the stitchless seam line forming acontinuous seam. The heat and pressure are applied in eitherspaced-apart intervals juxtaposed to the continuous seam, or in acontinuous manner to form a discontinuous stitchless seam therebyforming multiple seams along the strip. The multiple seams form a widthlocated across the area referred to as the seam region and runlongitudinally with the panels, as shown in FIGS. 1A-1F.

The layered panels are channeled under the wheel to produce a singlecontinuous fused cut weld which creates a continuous seam along the cutedge of the panels along with a discontinuous fused line which creates adiscontinuous seam 6 located adjacent to and in a direction that isparallel to the cut edge fuse.

A reinforcement 5 may be applied to strengthen the discontinuous seam 6.For instance, a reinforcement 5 such as a seam tape with a hot-meltpolyurethane adhesive, may be applied to the sealing region by heatingthe stitchless seam tape to a temperature sufficient to melt thepolyurethane adhesive and passing the tape and stitchless seam underpressure rollers in order to squeeze the molten adhesive onto theprotective layer surface so as to ensure good bonding of the tape to thesurface. The stitchless seam region may be reinforced by one or morereinforcements, including but not limited to tapes, threads, and textilelaminates. An additional cooling and quenching step may be performed toprovide a smooth seam. After a reinforcement seam tape is applied overthe discontinuous seam and cut weld, the heated reinforcement tape isthen cooled while undergoing the application of pressure to provide asmoother seam.

While particular embodiments of the present invention have beenillustrated and described herein, the present invention should not belimited to such illustrations and descriptions. It should be apparentthat changes and modifications may be incorporated and embodied as partof the present invention within the scope of the following claims. Thefollowing examples are offered for illustrative purposes, and are notintended to limit the scope of the invention.

EXAMPLE 1 Fuse Cut/Tape-ST78AU/Tricot

A liquid-proof stitchless seam was formed between two laminate panels inthe following manner.

A three-layer textile laminate was formed comprising a composite barriermembrane sandwiched between two textile layers. The composite barriermembrane was a composite of microporous polytetrafluoroethylene (PTFE)membrane coated with a polyurethane, prepared according to U.S. Pat. No.4,194,041 using a water vapor permeable, nonporous polyurethane coatingon the ePTFE. This membrane was laminated on one side, using a pluralityof dots of moisture curable polyurethane adhesive, to aPolyester/Spandex woven textile layer approximately 0.4 mm thick andhaving a weight of approximately 97 grams per square meter. The otherside of the membrane was laminated, again using a plurality of dots ofmoisture curable polyurethane adhesive, to a nylon tricot knit textileapproximately 0.6 mm thick and having a weight of approximately 38 gramsper square meter. Two panels having rough dimensions of about 0.15 m by0.7 m were then cut from this three-layer textile laminate.

The two panels were laid flat on a table on top of each other with thenylon/spandex textiles in contact with each other. A fused stitchlessseam was created along one edge of the layered laminate panels by movingthe layered panels between a rotating anvil and sonotrode. The layersare run so that the anvil simultaneously cuts and fuses the edge of thefabrics together to make what is commonly referred to as a butt weld.This weld was accomplished using a Lacemaster/Seammaster UltrasonicSewing Machine available from Sonobond Ultrasonics (West Chester, Pa.)equipped with an R1027 anvil. The machine was run under the followingconditions—speed equal to 2, amplitude equal to 10, and air pressure setat 60 psi. Both the anvil and sonotrode speed settings were kept thesame. The stitchless seam was made by running the layered panels on theright side of the wheel to produce a single continuous fuse line.

A 13 mm width stitchless seam tape (GORE SEAM® stitchless seam tapeobtained from W.L. Gore and Associates, Elkton, Md.), having a hot-meltpolyurethane adhesive, was then applied to the sealing region by heatingthe stitchless seam tape to a temperature sufficient to melt thepolyurethane adhesive and passing the tape and stitchless seam throughthe nip of a pair of pressure rollers in order to squeeze the moltenadhesive onto the protective layer surface so as to ensure good bondingof the tape to the surface. The resulting stitchless seam between thetwo laminate panels was tested using the Suter Test for Liquid-proofSeams and determined to be liquid proof based on passage of a 0.07 bar/3min challenge. The stitchless seam was then subjected to the Test forDurably Liquid-proof Seams, and after the wash/dry regimen, the sampleagain passed the 0.07/3 min challenge. As a further evaluation, thesample was then subjected to a more rigorous stitchless seam challengeof 3 psi (0.22 bar)/2 min in the Suter test rig, and no water wasobserved; thus, the sample remained durably liquid proof under the mostrigorous conditions. After further evaluation, it was found that thetextile outer surface had cracked and when the stitchless seam waspulled in a direction perpendicular to the direction of the stitchlessseam that the outer fabrics had separated.

EXAMPLE 2 Fuse Cut/Tape-ST78AU/Tricot

A liquid-proof stitchless seam was formed between two laminate panels ina manner substantially as described in Example 1, with the followingexceptions.

The two panels were laid flat on a table on top of each other with thenylon/spandex textiles in contact with each other. A fused stitchlessseam was created along one edge of the layered laminate panels by movingthe layered panels between a rotating anvil and sonotrode. The layersare run so that the anvil simultaneously cuts and fuses the edge of thefabrics together to make what is commonly referred to as a butt fuse.This fusing was accomplished using a Lacemaster/Seammaster UltrasonicSewing Machine available from Sonobond Ultrasonics (West Chester, Pa.)equipped with an R1027 anvil. The machine was run under the followingconditions—speed equal to 2, amplitude equal to 10, and air pressure setat 60 psi. Both the anvil and sonotrode speed settings were kept thesame. The stitchless seam was made by running the layered panels on theleft side of the wheel to produce a single continuous fuse line alongthe edge of the panels along with a discontinuous fuse locatedapproximately 0.8 mm in a direction that is perpendicular to thecontinuous fuse.

A 13 mm width stitchless seam tape (GORE SEAM® stitchless seam tapeobtained from W. L. Gore and Associates, Elkton, Md.), having a hot-meltpolyurethane adhesive, was then applied to the sealing region by heatingthe stitchless seam tape to a temperature sufficient to melt thepolyurethane adhesive and passing the tape and stitchless seam throughthe nip of a pair of pressure rollers in order to squeeze the moltenadhesive onto the protective layer surface so as to ensure good bondingof the tape to the surface. The resulting stitchless seam between thetwo laminate panels was tested using the Suter Test for Liquid-proofSeams and determined to be liquid proof based on passage of a 0.07 bar/3min challenge. The stitchless seam was then subjected to the Test forDurably Liquid-proof Seams, and after the wash/dry regimen, the sampleagain passed the 0.07/3 min challenge. As a further evaluation, thesample was then subjected to a more rigorous stitchless seam challengeof 3 psi (0.22 bar)/2 min in the Suter test rig, and no water wasobserved; thus, the sample remained durably liquid proof under the mostrigorous conditions. After further evaluation it was found that thetextile outer surface had not cracked and when the stitchless seam waspulled in a direction perpendicular to the direction of the stitchlessseam that the outer fabrics had not separated.

EXAMPLE 3

The seam strength of the samples manufactured in Example 1 and Example 2was evaluated using a modified grab break method. Five 4″×8″ sampleswere cut from each sample produced in Example 1 and Example 2 using aLab 500 USM Clicker Press (model SN-SE25 available from Hudson MachineryWorldwide). The cut sample was oriented so that the seam was parallel tothe direction of the 4″ sides. The seam was located approximately 4″ infrom the cut edge along the 8″ length and ran perpendicular to the 8″direction. Samples were mounted on an Instron tester (Instron Model 5565available from Instron Corporation) using a clamping fixture thatprovided a 1″ square of clamped area. A gap of 4″ was maintained betweenthe clamps. Care was take to locate the seam equidistant from each setof clamps as well as locating the center line of the clamps that runsperpendicular to the seam 2″ from the cut edge running in a directionperpendicular to the 8″ edge. Once mounted, the Instron tester applied aconstant displacement of 50 mm/min to the sample in a directionperpendicular to the seam direction. The Instron tester records the loadduring the displacement. The test was completed when a maximum load inNewton and percent strain were recorded when the seam broke.

Seam % Strain St. Strength (N) at Break Average Dev. Example 1 ST78AVCut-1 221 18 214 6 Example 1 ST78AV Cut-2 211 17 Example 1 ST78AV Cut-3215 17 Example 1 ST78AV Cut-4 218 17 Example 1 ST78AV Cut-5 206 16Example 2 ST78AV 1027T-1 262 19 261 5 Example 2 ST78AV 1027T-2 264 20Example 2 ST78AV 1027T-3 259 20 Example 2 ST78AV 1027T-4 254 19 Example2 ST78AV 1027T-5 266 19

1. A liquid-proof stitchless seam between panels comprising: a. a firstpanel comprising a functional liquid-proof layer; b. a second panelcomprising a functional liquid-proof layer; c. a discontinuous fusedstitchless seam connecting the first panel to the second panel; and d. areinforcement which strengthens the fused stitchless seam connecting thefirst panel to the second panel providing a liquid-impervious seam.
 2. Aliquid-proof stitchless seam between panels comprising: a. a first panelcomprising a functional liquid-proof layer; b. a second panel comprisinga functional liquid-proof layer; c. a discontinuous fused stitchlessseam connecting the first panel to the second panel; and d. a continuousfused stitchless seam positioned parallel to the discontinuous seam andconnecting the first panel to the second panel providing aliquid-impervious seam.
 3. The stitchless seam of claim 1 wherein thediscontinuous welded seam is an ultrasonic heat weld.
 4. The stitchlessseam of claim 1 wherein the reinforcement is a tape.
 5. The stitchlessseam of claim 1 wherein the reinforcement is a textile laminate.
 6. Thestitchless seam of claim 1 wherein the reinforcement is a non-fusedstitchless seam in conjunction with a sealing polymer.
 7. The stitchlessseam of claim 1 wherein the reinforcement is a sealing polymer.
 8. Thestitchless seam of claim 1 further comprising a second fused seam. 9.The stitchless seam of claim 8 where the second fused stitchless seam isa continuous heat-fused seam.
 10. The stitchless seam of claim 1 whereinthe reinforcement traverses the discontinuous fused seams and joins thefirst panel to the second panel.
 11. The stitchless seam of claim 1wherein the functional liquid-proof layer is a membrane.
 12. Thestitchless seam of claim 1 wherein the functional liquid-proof layercomprises ePTFE.
 13. A liquid proof stitchless seam comprising: a. afirst panel with a functional liquid-proof layer having an exteriorside, an interior side, and a designated stitchless seam edge; b. asecond panel with a functional liquid-proof layer having an exteriorside, an interior side, and a designated stitchless seam edge; and c. adiscontinuous bond connecting the designated stitchless seam edge of thefirst panel to the designated stitchless seam edge of the second panelin a stacked relation to each other so that the exterior sides of thepanels are bonded to each other with the bonded areas most distant fromthe stitchless seam edges of the panels forming a discontinuously bondedjoint on the plane formed by the exterior sides of the joined panels.14. The stitchless seam of claim 13 further comprising a continuous bondconnecting the designated stitchless seam edge of the first panel to thedesignated stitchless seam edge of the second panel in a stackedrelation to each other so that the exterior sides of the panels arebonded to each other.
 15. The stitchless seam of claim 14 wherein thecontinuous bond is oriented parallel the discontinuous bond.
 16. Thestitchless seam of claim 13 wherein the discontinuous bond is a heatfuse.
 17. The stitchless seam of claim 16 wherein the heat fuse isformed in a cross-hatch pattern.
 18. The stitchless seam of claim 16wherein the heat fuse is formed in a dotted pattern.
 19. The stitchlessseam of claim 16 wherein the heat fuse is formed in a sinusoidalpattern.
 20. The stitchless seam of claim 1 wherein the discontinuousfused stitchless seam is created using an ultrasonic fusing wheelcomprising a circumferential discontinuous embossing rib mounted on thewheel.
 21. The stitchless seam of claim 20 wherein the ultrasonic fusingwheel further comprises a circumferential cutting rib.
 22. Thestitchless seam of claim 21 wherein the circumferential cutting rib ismounted at least 0.1 mm from the discontinuous embossing rib.
 23. Thestitchless seam of claim 21 wherein the circumferential cutting ribprojects further outward from the wheel than does the discontinuousembossing rib.
 24. The stitchless seam of claim 21 wherein thecircumferential cutting rib and the discontinuous embossing rib areparallel to each other.
 25. The stitchless seam of claim 21 wherein thediscontinuous fused stitchless seam connecting the first panel to thesecond panel is applied at the same time as the panels are cut on thedesignated stitchless seam edge.
 26. The stitchless seam of claim 1wherein the stitchless seam has strength of at least 150 N.
 27. Thestitchless seam of claim 1 wherein the stitchless seam has strength ofat least 200 N.
 28. The method of forming a fused liquid-proofstitchless seam joining together pieces of liquid-proof laminate, saidmethod comprising: a. placing at least two pieces of a liquid-prooflaminate each having at least a textile layer and a liquid prooffunctional layer in stacked relation with textile regions in contactwith one another along a strip defining a stitchless seam line; and b.applying heat and pressure to the stacked laminates along said strip,the heat being applied continuously and the pressure being applied at aconstant interval most proximal to the edge of the stitchless seam lineforming a continuous stitchless seam and at spaced-apart intervalsjuxtaposed to the continuous stitchless seam to form a discontinuousstitchless seam thereby forming multiple seams along the strip.
 29. Themethod of claim 28 further comprising step c. cutting the stitchlessseam allowance.
 30. The method of claim 29 wherein step b. and c. arecarried on simultaneously.
 31. The method of claim 28 whereby saiddiscontinuous stitchless seam is weakly bonded relative to saidcontinuous seam.
 32. The method as defined in claim 28 wherein the heatapplied in step b.) is in the form of ultrasonic energy.
 33. The methodas defined in claim 28 wherein the pressure is applied by means of anembossed wheel.
 34. The method as defined in claim 28 wherein themultiple seams are reinforced by at least one reinforcement.
 35. Themethod as defined in claim 28 wherein the reinforcement is a tape. 36.The method as defined in claim 35 wherein the reinforcement is a thread.37. The method as defined in claim 35 wherein the reinforcement is atextile laminate.
 38. The method as defined in claim 28 wherein thefunctional layer is comprised of expanded PTFE.
 39. A fused stitchlessseam between at least two panels of laminates obtained by the method ofclaim
 28. 40. A fused stitchless seam between at least two pieces oflaminates obtained by the method of claim 28 wherein the fibers areheated and melted to different degree.